1. Field
Example embodiments of the following description relate to a cover opening and closing unit and an image forming apparatus including the same, and more particularly, to a cover opening and closing unit in which, when a cover is opened when a manual paper feed tray is opened, an angle of the manual paper feed tray with respect to the cover is adjusted so that sheets of paper do not fall, and an image forming apparatus including the same.
2. Description of the Related Art
In general, electrophotographic image forming apparatuses form a desired image by forming a desired electrostatic latent image on a photosensitive medium by using a light exposure unit, developing the electrostatic latent image as a toner image by using powder-type toner, transferring the toner image onto a recording medium by using a transferring medium, and fixing the toner image thereon.
Image forming apparatuses may include paper feed cassettes installed below a printing unit to be opened and closed and store sheets of paper and manual paper feed units installed at a side of the printing unit to be opened and closed for a sheet of paper to be manually fed by users. The manual paper feed unit may be rotatably attached to a cover. When the cover is opened, the manual paper feed unit may also be opened. The cover may be installed to easily remove jammed sheets of paper during printing or to open and close the image forming apparatus in order to replace parts constituting the printing unit.
When the manual paper feed tray is opened, a sheet of paper may be loaded on the manual paper feed tray. However, when the cover is opened when the manual paper feed tray is opened, the manual paper feed tray is moved together with the cover, and thus the sheet of paper loaded on the manual paper feed tray falls.
To address this problem, Japanese Patent Laid-Open Publication Nos. 2007-70044 and 2006-341987 discloses a method of preventing sheets of paper loaded on a manual paper feed tray from falling even though the manual paper feed tray is tilted, by attaching to the manual paper feed tray a separate device capable of fixing sheets of paper to the manual paper feed tray.
In addition, a structure in which a separate element such as wires is directly connected to a main body frame, and thus a manual paper feed tray is not tilted is disclosed in Japanese Patent Laid-Open Publication Nos. 2007-70044 and 2006-341987.
However, these methods incur high costs in raw materials and have complicated structures. In other words, in a case of a structure in which a manual paper feed tray is connected to a cover link, a plurality of links are used to maintain an angle of the manual paper feed tray with respect to a cover, resulting in complicated structures. A structure in which a manual paper feed tray is moved further downward and then upward when the cover is opened has a limitation that an angle at which the manual paper feed tray is opened is in the range of 70 degrees or less.